A little confused about the Duet.

[plasma]

Maybe its just late at night, but I am confused about how to use the Duet. If possible for one of the Duet users to chime in on some of the issues I am having.

1) is there an PID autotune command in the duet firmware, and if yes does it save the changes after it is done, or I have to manually enter the values some place.

2) On Rambo there is a Eeprom, on Smoothie there is a config text file and a M500 save command to override the config. Is there an equivelent in the Duet firmware? IE: If I need to change the z height on the duet in between the prints, do I have to modify the config file manually then reboot, or does the change become overwritten automatically?

3) What is the best practice to run a auto calibration of the Duet, and once its done does it automatically store the corrections? Or do I have to run the calibration every time I reboot the board.

Thanks

[mhackney]

There is no auto tune in the firmware. The wiki page on reprap has the process for tuning the heaters. The tuning is more accurate. Auto tune is being worked on. Also https://miscsolutions.wordpress.com/201 ... issioning/

For any parameter in RepRapFirmware you set it with a g- or m- code. That is temporary though - power off and you lose that setting. To persist the settings, you edit config.g and upload that to the Duet. The built in web interface makes it very simple to upload a new config.g. This may sound like more work but in practice it works very nicely and is quick. Basically, you can set the parameter you are working on in the web interface's input command line, test until you get it right and then simply copy/paste the command to the file and upload. This way, you do not make any changes to your working config.g file until you have tested and are comfortable with the changes so you always have a known good last state to fall back to.

There is no equivalent to M500 for RepRapFirmware yet, you either copy the config.g to the memory card or ftp it or upload via the web page (the easiest).

The auto cal is in the dc42 branch of the RepRapFirmware. It is so fast and easy that I run it at the start of every day and many times during the day for fine tuning. You basically bring the bed and hot end up to temperature first then issue a G32 and step back. If you use the web interface (which seriously you should consider doing since it is very nice) you can add the G32 to the menu at the top of the screen so it is easy to access. If you use the PanelDue display, there is a Calibrate button right on the main page. You home first (G28) then calibrate. Once the machine is calibrated I do not update the config.g file, there is no need to. The calibration is ready to go and if I turned off my machine for some reason, I simply recalibrate once it is powered back on and up to temperature. Takes <30 seconds to run the full 13 point calibration. If you want to store the calibration, you copy it to the config.g and reupload it. But I think you'll discover once you use this calibration it is so fast and easy that you'll use it much more frequently. I've even considered adding it to my gcode header to do it before every print. In that case, it really only adds 20 seconds since an entire G28 home can be eliminated and that takes more time.

[plasma]

Thank you Mhackney that was very helpful. Cant wait to get the build done and get to try out the Duet.

[plasma]

Michael,

The hotted fan, is there a way to program in the config file for it to turn on when the hot end reaches 50 degrees and turn off when it cools down?

Thanks
Vitaly

[mhackney]

"It depends!"

The Duet 0.8 supports this but requires the right firmware. David is working on this feature and it is in the new RepRapFirmware-1.09p-alpha2-dc42.bin firmware. It works great. It also has a fix for the inverted part fan so it now startsup turned off.

You'll need to add this to config.g:

; setup fan to be thermostatically controlled
M106 P1 T50 S255 H1

and you need to have the fan connected to the correct input as shown here:

The connector on the left is the part cooling fan, the one on the right is for the hotend cooling fan and is the one "P1" in the above code points to. More info on the wiki: http://reprap.org/wiki/G-code#M106:_Fan_On

[plasma]

Michael, Thank you again.

[Eaglezsoar]

Thanks Michael, I didn't know he released new software, I guess I will have to check more often.